A typical computing system includes one or more memory modules for storing software applications and program data, and a memory controller that controls access to the memory module under the direction of a microprocessor. Conventional memory modules, such as Single Inline Memory Modules (SIMMs) and Dual Inline Memory Modules (DIMMs), must be powered up and initialized with a predefined sequence of commands in order to operate properly. Failure to follow the required procedures for power up and initialization may result in undefined operation.
Most types of memory modules are designed to comply with one or more industry standards that specify a required initialization sequence for the particular memory type. Although most manufacturers of memory modules purport to conform to these industry standards, the exact initialization sequences required by the different manufacturers often have subtle variations. Two manufacturers of the same type of memory may, for example, require initialization sequences that include the same basic commands, but in a slightly different order. In addition, the manufactures may require different timings for applying the commands to the memory being initialized. For example, one manufacture may require that a command, such as a memory pre-charge command, be applied for a slightly longer or shorter duration than another manufacturer.
Conventional memory controllers are designed to apply a static initialization sequence in which the commands have of a fixed order and time duration. In other words, a memory controller may be designed to operate with a specific manufacturer. As a result, utilization of memory modules from other manufacturers may be difficult, and may require redesign of the memory controller or use of a different memory controller altogether.